The molecular mechanism by which Wnt signaling pathways regulate the growth of prostate cells has not been elucidated. Particularly, the identities of the receptors (Frizzled) that selectively express in prostate cancer cells are not known. Furthermore, the biological role Frizzleds play in mediating these signaling pathways during prostate cancer development and progression are not understood. Therefore, identification and characterization of the Frizzled proteins that selectively express in prostate cells and regulate the cell growth of prostate cancer will be very important for understanding the pathogenesis and progression of prostate cancer. The major of objective of this proposal is to investigate the expression and function of Frizzled proteins that are selectively expressed in prostate cancer cells in order to fully understand the biological role of the Wnt signaling pathway in the tumorigenesis of prostate cancer. Three specific aims are proposed in this fellowship, which include (1) Identification of the Frizzled proteins that selectively express in prostate cancer cell lines and prostate cancer tissues; (2) Investigate the biological role of Frizzled proteins in prostate cancer cells; (3) Study the biological role of Frizzleds in the pathogenesis of prostate cancer. [unreadable] [unreadable] [unreadable]